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Manual Pages  — RPC.LOCKD


rpc.lockd – NFS file locking daemon



rpc.lockd [-d debug_level] [-F] [-g grace period] [-h bindip] [-p port]


The rpc.lockd utility provides monitored and unmonitored file and record locking services in an NFS environment. To monitor the status of hosts requesting locks, the locking daemon typically operates in conjunction with rpc.statd(8).

Options and operands available for rpc.lockd:
  The -d option causes debugging information to be written to syslog, recording all RPC transactions to the daemon. These messages are logged with level LOG_DEBUG and facility LOG_DAEMON. Specifying a debug_level of 1 results in the generation of one log line per protocol operation. Higher debug levels can be specified, causing display of operation arguments and internal operations of the daemon.
  Run rpc.lockd in the foreground, rather than going into daemon mode. This is useful if some other process uses fork(2) and exec(3) to run rpc.lockd, and wants to monitor when and how it exits.
  The -g option allow to specify the grace period, in seconds. During the grace period rpc.lockd only accepts requests from hosts which are reinitialising locks which existed before the server restart. Default is 30 seconds.
-h bindip
  Specify specific IP addresses to bind to. This option may be specified multiple times. If no -h option is specified, rpc.lockd will bind to INADDR_ANY. Note that when specifying IP addresses with -h, rpc.lockd will automatically add and if IPv6 is enabled, ::1 to the list.
  The -p option allow to force the daemon to bind to the specified port, for both AF_INET and AF_INET6 address families.

Error conditions are logged to syslog, irrespective of the debug level, using log level LOG_ERR and facility LOG_DAEMON.

The rpc.lockd utility must NOT be invoked by inetd(8) because the protocol assumes that the daemon will run from system start time. Instead, it should be configured in rc.conf(5) to run at system startup.


  RPC protocol specification for the network lock manager protocol.


syslog(3), rc.conf(5), rpc.statd(8)


The implementation is based on the specification in

X/Open CAE Specification C218, ISBN 1 872630 66 9, Protocols for X/Open PC Interworking: XNFS, Issue 4,


A version of rpc.lockd appeared in SunOS 4.


The current implementation serialises locks requests that could be shared.

RPC.LOCKD (8) November 21, 2019

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